In consideration of the environment, attention has recently been given to a hybrid vehicle, an electric vehicle and the like that use electric power from a battery and the like to drive driving wheels.
Particularly in recent years, attention also has been given to wireless charging, by which the above-mentioned battery mounted in an electrically powered vehicle can be charged in a contactless manner without using a plug and the like. Furthermore, various types of charging schemes are also recently proposed as a contactless charging scheme.
The power transfer system using a contactless charging scheme is disclosed, for example, in Japanese Patent Laying-Open No. 2010-070048 (PTD 1), Japanese Patent Laying-Open No. 2010-252583 (PTD 2), Japanese Patent Laying-Open No. 2008-294385 (PTD 3), Japanese Patent Laying-Open No. 2009-004512 (PTD 4), and Japanese Patent Laying-Open No. 2009-076513 (PTD 5).
In these power transfer systems, a power transmission device and a power reception device each are configured to have a surface facing the other device through which electromagnetic waves can pass, and to have the other surfaces not facing the other device that are covered by a shield member. For example, a contactless power feeding system disclosed in PTD 1 employs a shield box having a cubic shape and configured to have a surface facing the other device so as to allow electromagnetic waves to pass therethrough, and to have other five surfaces each provided with a shield member so as to reflect the electromagnetic waves (near field).
The shield box should be sized such that a power feeding unit (a power transmission unit) and the shield member housed within the shield box are arranged at a certain distance or more from each other. Consequently, it is feared that the power feeding unit (power transmission unit) may be increased in size, particularly, increased in height.